This invention relates to a data processing control apparatus capable of effectively extracting from a record data comprised of a plurality of word data a necessary word data which is necessary for data processing.
Data as processed in a computer etc. comprises a record data which includes a plurality of word data, each word data including at least one character data. A main memory stores many such record data. That is, the main memory stores a plurality of serially arranged record data, each of which comprises a plurality of serially arranged word data. Each word data in the record data is serially read out by a readout instruction from the main memory in the order in which the record data are stored in the main memory. Out of each record data so read out from the main memory a specific word data is extracted for an arithmetic operation such as addition so that various data processing operations can be effected. That is, it is necessary to extract a specific word data from each record data during the readout of the record data from the main memory. A specific word extracting means is adapted to, for example, count the word data starting with the head of the record data and read out only a word data corresponding to a specific order. It is, however, difficult to effect such an operation during the readout of the record data from the main memory. Where a different word length is involved, such a control adds to complexity. A complicated control is also necessary in a case where a plurality of word data are extracted from one record data for data processing.
It is accordingly the object of this invention to provide a data processing control apparatus capable of selecting a word data from a record data read out from a main memory so as to effect data processing and capable of delivering only a selected word data to a data processing device.